This supercharger is superfrustrating. I don't understand why this one is being built prior to say Casa Grande? Maybe it's a permitting or approval issue, but Phoenix -> Flagstaff is totally doable in a 85 at this point, but you can't make it too far south.
It's doable if you 100% charge at Buckeye in an 85, have good weather, drive carefully, and don't have a bad headwind. That's too many ifs, and takes too long to charge at Buckeye; there is only so much time I want to spend at a Carl's Jr. Also, it is nearly impossible in a 60.
See the output below for an 85 on 21's carrying 400 lb (2 people with light luggage) from
EV Trip Planner. That is just a little too close for comfort.
My rule of thumb for fast, comfortable Supercharging in an 85, and doable in a 60, is to put the Superchargers about 133 miles apart, and reduce that amount by 6 miles per 1,000 feet for elevation differences between Superchargers. Because there are 5,800 feet between Buckeye and Flagstaff, that means the distance would have to be less than 98 miles; because it's actually 164 miles, without Cordes, you are 66 miles over budget.
For easy, fast charging, and no range anxiety in an 85 and any possibility in a 60, Cordes is very needed. That in no way reduces the need for Casa Grande; they are both needed.